Optical beam steering using liquid-based devices

Non-mechanical optical beam steering has received extraordinary attention in recent decades because it can steer a beam to a desired direction or location without moving parts. As a novel member of the non-mechanical beam steering method family, the liquid-based beam steering method exhibits some intriguing features. For example, this method is polarization-independent and has wide broadband, low power consumption, simple structure, and long lifetime. Many studies have been devoted to realizing optical beam steering based on liquid-based devices. This paper reviews the recent progress in this field. First, from the perspective of the working principles, the technical approaches are divided into the following four types: electrowetting effect, dielectrophoresis effect, tunable liquid lenses, and hydraulic control. The optical beam steering using liquid-based devices based on the electrowetting effect is reviewed from multiple aspects, including different sidewall shapes, multiple actuation electrodes, multiple liquid-liquid interfaces, and droplet movement. Moreover, the performances of the optical beam steering using liquid-based devices are compared, which provide a reference for readers to select the working principle to design the beam steering devices. Next, some representative applications of the beam steering device using liquid-based devices are presented, including optical switch, three-dimensional display, laser radar, solar tracking, indoor light, and microscopy. Finally, the challenges and outlook of optical beam steering using liquid-based devices are discussed. This review aims to provide a snapshot of the current state of the research field of optical beam steering using liquid-based devices to attract additional attention.

Automated summary

The non-mechanical optical beam steering method using liquid-based devices has gained attention for its unique advantages such as polarization independence, wide broadband, low power consumption, and long lifetime. This review provides insights into the working principles, performance comparisons, representative applications, challenges, and future prospects of optical beam steering using liquid-based devices, aiming to attract more attention to this research field.